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<H1>ADC -- Add with Carry</H1>

<PRE>
Opcode    Instruction      Clocks    Description

14 ib     ADC AL,imm8      2         Add with carry immediate byte to AL
15 iw     ADC AX,imm16     2         Add with carry immediate word to AX
15 id     ADC EAX,imm32    2         Add with carry immediate dword to EAX
80 /2 ib  ADC r/m8,imm8    2/7       Add with carry immediate byte to r/m
                                     byte
81 /2 iw  ADC r/m16,imm16  2/7       Add with carry immediate word to r/m
                                     word
81 /2 id  ADC r/m32,imm32  2/7       Add with CF immediate dword to r/m
                                     dword
83 /2 ib  ADC r/m16,imm8   2/7       Add with CF sign-extended immediate
                                     byte to r/m word
83 /2 ib  ADC r/m32,imm8   2/7       Add with CF sign-extended immediate
                                     byte into r/m dword
10 /r     ADC r/m8,r8      2/7       Add with carry byte register to r/m
                                     byte
11 /r     ADC r/m16,r16    2/7       Add with carry word register to r/m
                                     word
11 /r     ADC r/m32,r32    2/7       Add with CF dword register to r/m dword
12 /r     ADC r8,r/m8      2/6       Add with carry r/m byte to byte
                                     register
13 /r     ADC r16,r/m16    2/6       Add with carry r/m word to word
                                     register
13 /r     ADC r32,r/m32    2/6       Add with CF r/m dword to dword register
</PRE>

<H2>Operation</H2>

<PRE>
DEST := DEST + SRC + CF;
</PRE>

<H2>Description</H2>

ADC performs an integer addition of the two operands DEST and SRC and the
carry flag, CF. The result of the addition is assigned to the first operand
(DEST), and the flags are set accordingly. ADC is usually executed as part
of a multi-byte or multi-word addition operation. When an immediate byte
value is added to a word or doubleword operand, the immediate value is first
sign-extended to the size of the word or doubleword operand.

<H2>Flags Affected</H2>

OF, SF, ZF, AF, CF, and PF as described in <A HREF="appc.htm">Appendix C</A>

<H2>Protected Mode Exceptions</H2>

#GP(0) if the result is in a nonwritable segment; #GP(0) for an illegal
memory operand effective address in the CS, DS, ES, FS, or GS segments;
#SS(0) for an illegal address in the SS segment; #PF(fault-code) if page
fault

<H2>Real Address Mode Exceptions</H2>

Interrupt 13 if any part of the operand would lie outside of the effective
address space from 0 to 0FFFFH

<H2>Virtual 8086 Mode Exceptions</H2>

Same exceptions as in Real Address Mode; #PF(fault-code) for a page fault


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<B>up:</B> <A HREF="c17.htm">
Chapter 17 -- 80386 Instruction Set</A><BR>
<B>prev:</B><A HREF="AAS.htm"> AAS ASCII Adjust AL after Subtraction</A><BR>
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